Furnace-grate.



T. DAWSON.

FURNAGE GRATE.

APPLICATION FILED MAR. 23,1909.

Patented May 3, 1910.

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THOMAS DAWSON, OF LIVINGSTON MANOR, NEW YORK.

FURNACE-GRATE.

To all whom it may concern:

Be it known that I, THOMAS Dawson, a citizen of the United States, residing at Livingston Manor, in the county of Sullivan and State of New York, have invented or discovered certain new and useful Improvements in Furnace-Grates, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to grates for furnaces, and more particularly to that class of furnaces in which fine granular fuel, such as buckwheat coal, is used, such as retort furnaces and the like; and the invention has for its object to provide a grate construction of such a character that the grate bars may be shaken or rocked, in clearing the fire box of ashes, without vertically vibrating the body of burning fuel in the shaking operation.

Another object of the invention is to provide a grate construction which may be readily applied to existing furnaces without requiring the same to be torn away, and also to provide rocking grate bars which may be readily taken out when it is necessary to replace them.

In the accompanying drawings Figure 1 is a vertical longitudinal section illustrative of the present invention. Fig. 2 is a plan view of the rocking grate bars and their supporting frame. Fig. 3 is a transverse section of the invention. Fig. 4 is a detail view showing an end tenon of one of the cross-bars of the supporting frame, and the tapering mortise in the side bar in which said tenon fits.

Referring to the drawings, 12 denotes the side bars of the frame in which the rocking grate bars 13 are mounted, said side bars be ing provided with open-topped slots 14k and being adapted to rest on suitable supports within the furnace walls. The side bars 12 are joined at or near their ends by cross bars 15 having dove-tailed tenons 16 at their ends entering dove-tailed mortises 17 in the said side bars, said tenons and mortises being wedge-shaped or tapered downwardly, as shown in the detail view Fig. 4, so that said cross bars may be readily inserted in their mortises from above, and by the dove-tailed and wedge-shaped construction of the said Specification of Letters Patent.

Application filed March 23, 1909.

Patented May 3, 1910. Serial No. 485,332.

side bars 12 and rest on the walls at the bot-- toms of said slots. The upper walls of said grate bars 13 are provided with a series of slots 19 permitting the entrance of air from beneath, and also permitting ashes to be shaken through said bars. By reference to Figs. 2 and 3 it will be seen that each of the said grate bars is formed hollow, like an inverted trough, with a concave recess or chamber beneath, and said grate bar is provided with heads 20 closing said recess or chamber at its ends and from which end heads the pivot pins 18 of the said bars project, and each of said bars is provided at its central portion with a web 21 filling the concave chamber of the grate bar crosswise and having a downwardly extending operating arm or portion 22. The end heads 20 and the central transverse web 21 serve to strengthen and brace the said hollow bars and prevent them from warping, each of said bars with its end heads and central web being preferably cast in one piece.

At the front of the furnace is a bracket 23 which pivotally supports a lever 24 which is ointed at its lower end to links or bars 25 provided with pins 26 engaging the depending operating arms 22 of the webs 21 on the grate bars. The operating arms of the rear end grate bar is provided with a hole through which one of the pins 26 passes to sustain the rear ends of the links or bars 25,

but the depending arms 22 of the other grate bars are preferably forked to engage the pins 26. This forked construction of the operating arms of the grate bars permits said bars to be inserted or removed from above without disturbing the other parts, as will be understood. The operating lever 24: is preferably provided with a removable handle section 27, which may be attached to the body of the lever in any suitable manner, but which is preferably provided at its lower end. with a socketengaging a tenon or projection 28 on the upper end of the said lever. By providing the operating lever with a removable handle portion such portion may be kept cool, and will thus not become too hot to handle; and when not in use it will be out of the way from in front of the furnace door.

It will be observed that the operating arms 22 of the grate bars are arranged cen trally of the lengths thereof, so that in shaking the grate the power for such purpose will be applied centrally of the grate bars so that there will be no tendency to twist the operating arms out of shape, and by thus applying the shaking power to the central. portions of the grate bars the latter will have no tendency to bind when being rocked.

In the construction herein shown the invention is illustrated as being applied to a furnace having a fire box of rectangular form in plan view, but if the invention is to be applied to a furnace having a round fire box or combustion chamber the side bars of the frame supporting the rocking grate bars may be curved horizontally, and the grate bars, instead of being all of one length, as herein shown, will be of different lengths to fit between the horizontally curved side bars of the frame.

From the foregoing it will be understood that the invention provides a furnace grate in which the grate bars are removably mounted so that they may be readily replaced when burned out, and in which the rocking grate bars are so mounted that the grate may be readily shaken when desired, the grate bars being of such construction, with their curved upper surfaces, as not to objectionably disturb the burning mass of fuel by shaking the same up and down in the operation of clearing the grate of ashes.

Having thus described my invention I claim and desire to secure by Letters Patent 1. A hollow slot-ted grate bar for furnaces formed convex on its upper side and provided with a concave chamber beneath, said grate bar having heads closing said concave chamber at its ends, said end heads being provided with pivots, so that said bar may rock in a fulcrum which is within the horizontal plane of said heads, and said gratebar having an intermediate transverse strengthening web filling said concave chamber crosswise and being provided with a downwardly extending operating arm.

2. A hollow slotted grate bar for furnaces cast in a single piece and formed convex at its upper side and provided with a concave chamber beneath, said grate bar having end heads provided with pivots, so that said bar may rock on a fulcrum which is within the horizontal plane of said heads, said grate bar having an intermediate transverse strengthening web filling said concave chamber crosswise and being provided with a downwardly extending operating arm, said end heads closing the ends of said chamber and serving, in cooperation with said intermediate web, to stiffen the hollow grate bar and prevent the same from warping.

3. In a furnace grate, the combination with a frame, comprising side bars having open-topped slots, of a series of hollow rocking grate bars having end heads provided with pivotpins loosely fitting in said slots, said bars being thus adapted to rock on fulcrums which are within the horizontal plane of said heads, and each of said grate bars being hollow and having transverse slots and a curved upper surface, a concave lower surface, to provide a recess or chamber, and a centrally disposed transverse strengthening web filling said chamber crosswise and being provided with a depending operating arm, an operating lever for shaking the grate, and links or bars jointed to said operating lever and provided with pins engaged by the operating arms of said rocking grate bars.

4. In a furnace grate, the combination with a frame comprising side bars having open topped slots, of a series of hollow rocking grate bars having end heads provided with pivot pins loosely fitting in said slots, said bars being thus adapted to rock on fulcrums which are within the horizontal plane of said heads, and each of said grate bars having a convex slotted upper surface, a concave lower surface to form a chamber, and a centrally disposed transverse strengthening web filling said chamber crosswise and being provided with a depending operating arm having an open slot at its lower end, an operating lever for shaking the grate, and links or bars ointed to said oper ating lever and provided with pins engaged by the slotted lower end portions of the said operating arms of said grate bars.

In a furnace grate, the combination with a frame comprising side bars having open topped slots, of a series of hollow rocking grate bars having end heads provided with pivot pins loosely fitting in said slots, said bars being thus adapted to rock on fulcrums which are within the horizontal plane of said heads, and each of said grate bars having a convex, slotted upper surface, a concave lower surface to form a chamber, a centrally disposed transverse strengthening web filling said chamber crosswise and being provided with a depending operating arm having an open slot at its lower end, an operating lever for shaking the grate, and links or bars jointed to said operating lever and provided With pins engaged by the slotted portions of the said operating arms of said grate bars said operating lever having a removable handle.

In testimony whereof I afiix my signature, 1n presence of two wltnesses.

THOMAS DAWSON.

Witnesses:

BENJ. E. DEvoY, J r., EDWARD D. YORK. 

